Aspirin is metabolised to salicylic acid (SA) in the body. SA is a plant hormone found in many common food plants. I wonder if some of the health benefit of a plant-heavy diet can come from the SA. Maybe we are adapted to a certain level of SA intake, and eating aspirin helps us fulfill our SA "requirement" ... and then some, a baby Aspirin gives us 10-100x as much SA as a day's worth of plant-based food.